Innovation Associates proposes to develop and validate a fiber optic sensor for measuring lead in blood which can measure 1-100 micro g/dL concentrations of lead in blood using an innovative Lead Ion Selective Fiber Optode (LISFO) technology. The proposed sensor will require a blood volume less than 200 micro L and will be capable of repeated sample analysis every 3 minutes. It will operate with an accuracy and a precision of 5-10% or better when measuring 10 micro g/dL lead concentrations. This will make the instrument suitable for lead screening programs under the new CDC guideline of 10 micro g/d. Use of fiber optic technology will provide a rugged, compact portable instrument and will allow low cost screenings of blood lead concentrations to be performed. Sample preparation will be automated so that minimally trained operators can achieve reliable results with minimal opportunity for sample contamination. The electronic output from the device will be designed to interface with a PC so that an entered patient ID will be printed together with the test results. The sensor will utilize elements which have been individually validated in other systems, but which have heretofore not been combined.